TUNNEL DISASTER PREVENTION SYSTEM

PROBLEM TO BE SOLVED: To provide a tunnel disaster prevention system which enables a fire detector to normally perform fire monitoring by suppressing influence on the whole system even when disconnection and/or short circuit occur between the fire detector and a repeater.SOLUTION: A tunnel disaster prevention system 1 includes: individual trunk lines composed of two trunk lines of a main trunk line and sub trunk line (first main trunk line 13a and first sub trunk line 13b, second main trunk line 17a and second sub trunk line 17b); and a repeater 7. The repeater 7 comprises: a transmission/reception circuit 21 for transmitting/receiving signals to/from a disaster prevention reception board 3 and a plurality of fire detectors (first fire detector 9, second fire detector 11); first switching means 23 and second switching means 25 which are provided between the transmission/reception circuit 21 and the respective trunk lines and switch connection states between the transmission/reception circuit 21 and respective fire detectors to connection/disconnection states for each main trunk line and sub trunk line; monitoring means 28 for monitoring the state of the respective fire detectors to detect normality/abnormality; and a switching control unit 29 for controlling switching of the switching means. 【課題】火災検知器-中継器間に断線及び／又は短絡が発生した場合でも、システム全体に与える影響を小さく抑えて火災検知器が正常に火災監視できるトンネル防災システムを提供する。【解決手段】本発明に係るトンネル防災システム１は、個別の幹線が主幹線と副幹線（第１主幹線１３ａと第１副幹線１３ｂ、第２主幹線１７ａと第２副幹線１７ｂ）の２つの幹線からなり、中継器７は、防災受信盤３及び複数の火災検知器（第１火災検知器９、第２火災検知器１１）と信号を送受信する送受信回路２１と、送受信回路２１と各幹線との間に設けられて、送受信回路２１と各火災検知器との接続状態を、主幹線及び副幹線ごとに接続／非接続に切り替える第１スイッチング手段２３及び第２スイッチング手段２５と、各火災検知器の状態を監視して正常・異常を検出する監視手段２８と、スイッチング手段の切り替えを制御する切替え制御部２９とを備えたことを特徴とするものである。【選択図】 図１